Mazda CX-9 Grand Touring. Manual - part 264

CONDITION 



The test fails when the PCM detects an intermittent signal from the CMP 
sensor (LH).  

POSSIBLE CAUSE 



Connector or terminal malfunction  



CMP sensor (LH) malfunction  



Sensor shielding malfunction  



Short to ground circuit between CMP sensor (LH) terminal A and PCM 
terminal 2AB  



Short to power supply between CMP sensor (LH) terminal A and PCM 
terminal 2AB  



Open circuit between CMP sensor (LH) terminal A and PCM terminal 2AB 



Open circuit between CMP sensor (LH) terminal B and PCM terminal 2C  

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 189 

© 2005 Mitchell Repair Information Company, LLC. 

DIAGNOSTIC PROCEDURE 

DTC P0349 (MZI-3.7) DIAGNOSTIC PROCEDURE 

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS 
BEEN RECORDED  



Has FREEZE FRAME DATA been 
recorded?  

Yes Go to the next step.

No

Record FREEZE FRAME DATA on the repair 

order, then go to the next step.

VERIFY RELATED REPAIR 

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 190 

© 2005 Mitchell Repair Information Company, LLC. 

2

INFORMATION AVAILABILITY  



Verify related Service Bulletins and/or 
on-line repair information availability. 



Is any related Service Bulletins 
available?  

Yes

Perform repair or diagnosis according to the 
available Service Bulletins. 



If the vehicle is not repaired, go to the 
next step.  

No

Go to the next step.

3

CLEAR AND ATTEMPT TO RETRIEVE 
THE DTC 

 



Clear the DTC from the PCM memory 
using the M-MDS.  



Turn the ignition switch to the ON 
position (Engine running).  



Increase engine speed to more than 
1,500 rpm for 10 s. Repeat this 3 
times.  



Retrieve the continuous memory 
DTCs.  



The same DTC present?  

NOTE:



If DTCs P0340, P0344, P0345 or 
P0349 are present, ignition, 
alternator noise, radio frequency 
interference and CKP concerns 
should be considered.  

Yes Go to the next step.

No

Perform the "INTERMITTENT CONCERN 

TROUBLESHOOTING". Then go to Step 11.

4

CHECK THE GENERATOR FOR 
EXCESSIVE ELECTRICAL NOISE 

 



Turn the ignition switch to the ON 
position (Engine running).  



Monitor the generator for an audible 
electric noise.  



Turn the ignition switch off.  



Generator/regulator terminal B 
disconnected.  

NOTE:



If the generator/regulator is 
electrically noisy, the noise 
decreases when the terminal B is 
disconnected.  

Yes Go to the next step.

No



Inspect the charging system, then go to 

Step 11. 



Drive belt damaged and 

misinstallation  



Generator pulley or generator 

misinstallation  

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 191 

© 2005 Mitchell Repair Information Company, LLC. 



Turn the ignition switch to the ON 
position (Engine running).  



With the engine running, determine if 
the generator is still noisy.  



Does the noise remain constant when 
the terminal B is disconnected?  

5

INSPECT CMP SENSOR (LH) 
CONNECTOR FOR POOR 
CONNECTION  



Turn the ignition switch off.  



Disconnect the CMP sensor (LH) 
connector.  



Inspect for poor connection (such as 
damaged/pulled-out pins, corrosion).  



Are there any malfunction?  

Yes

Repair or replace suspected part, then go to Step 
11.

No

Go to the next step.

6

INSPECT CMP SENSOR SIGANAL 
CIRCUIT FOR SHORT TO POWER 
SUPPLY  



Turn the ignition switch to the ON 
position (Engine off).  



Measure voltage between CMP sensor 
(LH) terminal A (wiring harness-side) 
and body ground.  



Is the voltage B+?  

Yes

Repair or replace suspected part, then go to Step 
11.

No

Go to the next step.

7

INSPECT CMP SENSOR (LH) SIGNAL 
CIRCUIT FOR SHORT TO GROUND  



Turn the ignition switch off.  



Check continuity between CMP sensor 
(LH) terminal A and body ground.  



Is there continuity?  

Yes

Repair or replace suspected part, then go to Step 
11.

No

Go to the next step.

8

INSPECT PCM CONNECTOR FOR 
POOR CONNECTION  



Turn the ignition switch off.  



Disconnect PCM connector.  



Check for poor connection (such as 
damaged, pulled-out pins, and 
corrosion).  



Are there any malfunction?  

Yes

Repair or replace suspected part, then go to Step 
11.

No

Go to the next step.

INSPECT CMP SENSOR (LH) CIRCUIT 

 

2008 Mazda CX-9 Grand Touring 

2008 ENGINE PERFORMANCE On-Board Diagnostic (MZI-3.7) - Mazda CX-9

  

Microsoft 

 

Sunday, November 15, 2009 10:08:37 AM

Page 192 

© 2005 Mitchell Repair Information Company, LLC.